Use this node to model inflow of heat through a virtual domain, at inlet boundaries of nonsolid domains. The upstream temperature Tustr and upstream absolute pressure pustr are known at the outer boundary of the virtual domain. The inflow condition is often similar to a temperature condition. However, using this condition, the upstream temperature is not strictly enforced at the inlet. The higher the flow rate, the smallest the difference between the inlet temperature and the upstream temperature. In case of heat sources or temperature constraints close to the inlet boundary, the inflow condition induces a temperature profile that approaches the temperature profile that would be obtained by computing the solution in the virtual domain upstream the inlet.

where ΔH is the sensible enthalpy. See Theory for the Inflow Boundary Condition in the Heat Transfer Module User’s Guide for details.

The Upstream temperature Tustr should be specified. For User defined, enter a value or expression. Else, select any available input (like Ambient temperature defined in an Ambient Properties node under Definitions).

Select the Specify upstream absolute pressure checkbox to set a different value than the absolute inlet pressure for the Upstream absolute pressure pustr, and account for work done by pressure forces in the expression of the enthalpy. For User defined, enter a value or expression. Else, select an Ambient absolute pressure defined in an Ambient Properties node under Definitions.